ST供应商提供的stm32l（低功耗系列）芯片的时钟配置工具，stm32l系列和以往的配置方式不一样，文档中附有成功设置的例子。-Stm32l ST suppliers (low-power series) chip clock configuration tool, stm32l series and not the same as the previous configuration, documentation with examples of successful setup.